1. Field of the Invention
The present invention relates to a liquid sprayer capable of simultaneously dispensing multiple liquids from multiple liquid reservoirs and having a dual action venting means for relieving back pressure in the liquid reservoirs as the liquid is dispensed while preventing leakage or evaporation of fluids.
2. Description of the Related Art Including Information Disclosed Under 37 CFR .sctn..sctn.1.97-1.99
Heretofore, various apparatus for dispensing multiple liquids simultaneously have been proposed. Several examples of analogous and non-analogous multiple liquid sprayer assemblies are disclosed in the following U.S. Patents:
______________________________________ U.S. Pat. No. Patentee ______________________________________ 4,355,739 Vierkotter 5,009,342 Lawrence et al. 5,152,461 Proctor 5,398,846 Corba et al. 5,439,141 Clark et al. ______________________________________
The Vierkotter, U.S. Pat. No. 4,355,739 discloses a liquid storage container that can be connected or attached to a spray pump which comprises two separate chambers for holding liquid components. Each chamber has a liquid draw tube which leads to a mixing chamber contained within a movable member attached to a movable external selector. As the movable member is rotated the openings for transferring liquid between the two separate chambers and the spray pump overlap to a varying degree to alter the ratio at which the two liquids are mixed prior to dispensing.
The Lawrence et al., U.S. Pat. No. 5,009,342 discloses a dual liquid sprayer assembly having a spray pump dispenser, a container having at least two separate compartments, and a valve assembly located between the spray pump dispenser and the container. The valve assembly has an inner valve member and an outer valve member capable of rotating with respect to one another. The outer valve member is capable of connecting one or more of several input passageways to an output passageway connected to the pump dispenser. Each input passageway is associated with a separate fluid compartment within the container. The input passageways can be connected with a variable size opening to allow the multiple fluids to be dispensed in different ratios.
The Proctor, U.S. Pat. No. 5,152,461 discloses a trigger sprayer which selectively draws fluid out from at least two containers, mixes the fluids, and dispels the fluids out of a nozzle. The trigger sprayer is equipped with a metering device for variably controlling the ratio of the fluids being mixed. Each container is selectively detachable for refilling the container with fluid or for attaching another container having an alternate fluid.
The Corba et al., U.S. Pat. No. 5,398,846 discloses a trigger sprayer capable of simultaneous dispensing of fluids from multiple containers in a pre-determined ratio. The trigger sprayer assembly includes a valve member and a fluid transfer member between the pump sprayer and at least two fluid containers. The valve member and the fluid transfer member rotate with respect to one another for selectively connecting the fluid passageways associated with each fluid container to the intake port of the pump sprayer. The valve member and the fluid transfer member additionally instantaneously open and close venting passageways between the fluid containers and the ambient atmosphere.
The Clark et al., U.S. Pat. No. 5,439,141 discloses a manifold for use with a trigger sprayer. The manifold allows the pump sprayer to draw fluid simultaneously from two separate reservoirs containing different fluids. The manifold includes at least one ball check valve. The ball check valve prevents the pumping of fluid from one of the reservoirs when the other reservoir is empty.
Heretofore, various apparatus for relieving back pressure in the liquid reservoirs as the liquid is dispensed while preventing leakage of fluids have been proposed. Several examples of analogous and non-analogous apparatus for venting the interior of liquid reservoirs while preventing leakage of fluids are disclosed in the following U.S. Patents:
______________________________________ U.S. Pat. No. Patentee ______________________________________ 4,072,252 Steyns et al. 4,618,077 Corsette ______________________________________
The Steyns et al., U.S. Pat. No. 5,072,252 discloses a trigger sprayer having a plunger type pump. The plunger type pump has a piston which moves within a bore in the housing of the pump sprayer. A sealing means is located around the piston. The sealing means prevents air or liquid located behind the piston inside the trigger sprayer body from escaping into the ambient atmosphere. Air or liquid located on the other side of the sealing means is exposed to the ambient atmosphere. A venting passage has one end connected to the liquid container and a second end connected to the bore containing the piston with the sealing means. As the piston moves back and forth within the chamber, the sealing means travels over the end of the venting passage exposing the venting passage to the ambient atmosphere.
The Corsette, U.S. Pat. No. 4,618,077 discloses a trigger sprayer having a plunger type pump. The plunger type pump has a piston which moves within a bore in the housing of the pump sprayer. A sealing structure is located near the end of the piston. A venting passage provides a path between the liquid containers and the bore within the pump sprayer. When the piston is in an uncompressed position, the sealing structure prevents air or liquid located behind the sealing structure from communicating with the ambient atmosphere. As the piston moves into a compressed position within the bore, the sealing structure encounters a rib which deforms the sealing structure sufficiently to allow either liquid or air to move around the sealing structure. While the sealing structure is deformed air from the ambient atmosphere is allowed to enter the venting passage. As the piston moves into an uncompressed position the sealing structure re-establishes the seal.